1. Field of the Invention
The present invention relates to a conductive contact unit and a conductive contact that are brought into contact with an electrode or a terminal that transmits and receives an electrical signal upon testing a conductive state or testing operating characteristics of an electronic component such as a liquid crystal panel or a semiconductor integrated circuit.
2. Description of Related Art
In a technological field of electrical characteristic testing of a test object such as a semiconductor integrated circuit, there is a known technology related to a conductive contact unit. The conductive contact unit includes a plurality of conductive contacts, each of which is arranged correspondingly to a connecting terminal of the semiconductor integrated circuit, and provides electrical conductivity by bringing the conductive contacts into physical contact with the connecting terminals. A structure of the conductive contact includes at least the conductive contacts and a conductive contact holder for holding the conductive contacts. Along with a trend to miniaturize the semiconductor integrated circuit that is a test object, various technologies have been suggested for the conductive contact unit to narrow the intervals between the arranged conductive contacts so that smaller intervals of connecting terminal arrangement can be accommodated.
As one of the examples of the conductive contacts that achieve narrower arrangement intervals, there has been suggested a plate-shaped conductive member structure that is integrated with a contacting element that is brought into contact with the test object, and an elastic element that urges a snapping force to the contacting element. By arranging the plate-like conductive contacts in a through-thickness direction, it becomes theoretically possible, according to this technology, to arrange a number of conductive contacts in a small space. In this manner, a conductive contact that can support the narrower arrangement intervals of the connecting terminals of the test object can be achieved. (For example, see Patent Document 1 listed below.)
[Patent Document 1] Japanese Patent Application Laid-open Number 2001-343397
The structure of the known conductive contact unit having the plate-like conductive contacts includes a conductive contact holder with guiding holes formed thereon for containing the conductive contacts. In this structure, the intervals of the arranged conductive contacts are defined by intervals between the guiding holes that are provided correspondingly to the number of the conductive contacts. However, minimum possible intervals thereof are limited by several conditions, such as physical strength of the conductive contact holder on which these guiding holes are formed. Therefore, even though the conductive contacts themselves have a structure suitable for smaller arrangement intervals, not sufficient devices have been suggested for the structure of the conductive contact holder. Therefore, considering the conductive contact unit as a whole, it has been sometimes difficult to reduce the arrangement intervals of the conductive contacts.
Upon performing a test using the known conductive contact unit, it is preferable for an operator using the conductive contact unit to be able to visually check the contact between the tip of the conductive contact and the test object. However, in the known conductive contact unit, when the conductive contact is looked down from the top, lower tip of the conductive contact is positioned inside a side wall of the conductive contact holder. Therefore, to observe the contact between the tip area of the conductive contact and the test object, the operator needed to bend over and look into the contact area. This leads to an increased physical burden to the operator when the greater number of times the test is performed.
Furthermore, in the known conductive contact unit, the tip of the conductive contact makes a stroke in a direction substantially in parallel with the direction in which the elastic bodies are extended. Therefore, it has been impossible to sufficiently remove an oxidized film formed on the surface of the test object, or dust attached thereon. Therefore, it has been sometimes impossible to obtain a stable electric contact. In such a situation, an excessive load could be applied onto the conductive contacts.